SYDNEY, Feb 15 (Reuters) - Australia’s only listed residential realtor McGrath Ltd swung to a first-half loss, with the departure of a fifth of its agents setting the company back by millions of dollars in sales and a writedown.

It was McGrath’s worst six-month performance since its IPO in December 2015, underscoring the challenges it faces as it battles not only its personnel issues but also higher taxes and tighter lending that have forced the country’s red-hot property market to pause.

“I can’t comment on the circumstances that led to the previous board of management to make the decision to IPO (but) I can comment on the results ... today and clearly we’ve disappointed shareholders,” outgoing CEO Cameron Judson said.

It will take time to rebuild the “quality of the cohort” Judson told Reuters by phone, referring to the 52 agents, out of 240, who left the company in the past year.

Judson will step down as CEO on Friday.

Founder and 26-percent owner John McGrath will step in as interim executive chairman.

Judson’s departure - and that of McGrath’s chairman, company secretary and three directors - was announced last month in a statement, which also flagged that the company would report a loss for the six months ended December.

McGrath posted a A$26 million half-yearly net loss, versus a profit of A$2.7 million a year ago, hit by a A$22 million ($17 million) writedown on the carrying value of its sales unit.

Revenue fell by nearly a quarter as the total value of home sales slumped to A$2.6 billion from A$3.5 billion.

McGrath’s IPO coincided with the end of a property boom which saw home values in the two biggest cities, Sydney and Melbourne, double in the eight years to 2017.

But a host of government interventions intended to curb foreign home purchases and help along housing affordability began to take effect by late 2017 and drove down Sydney home prices in December.

Shares of the realtor have shed 80 percent of their value since their debut, closing at 43 cents on Wednesday, compared to an A$2.10 issue price.

The shares were in a trading halt on Thursday after the company said it planned “an announcement regarding recent media comment in relation to Mr McGrath”.

On Feb. 8, the company issued a statement denying local reports that the founder had a loan facility secured against his company shares. The company has also previously denied reports that McGrath had an undisclosed personal gambling debt.

A company spokeswoman declined to comment further on either allegation on Thursday.